check-imports.go

package main

import (
	"bufio"
	"fmt"
	"os"
	"path/filepath"
	"strings"
)

func main() {
	dir, err := os.Getwd()
	if err != nil {
		panic(err)
	}

	project := strings.Split(dir, "/src/")[1]
	project = strings.Join(strings.SplitN(project, "/", 3)[:3], "/")

	var invalidImports []string
	err = filepath.Walk(".", func(path string, info os.FileInfo, err error) error {
		if strings.Contains(path, "vendor/") {
			return filepath.SkipDir
		}
		if info.IsDir() {
			return nil
		}

		if !strings.HasSuffix(info.Name(), ".go") {
			return nil
		}

		f, err := os.Open(path)
		if err != nil {
			return err
		}
		defer f.Close()
		var prevGroup string
		var importGroups string
		started := false
		reader := bufio.NewReader(f)
		for err == nil {
			var line string
			line, err = reader.ReadString('\n')
			if !started {
				started = strings.HasPrefix(line, "import (")
				continue
			}
			if strings.HasSuffix(line, ")\n") {
				break
			}
			iType := identifyImportType(project, line)
			if prevGroup != iType {
				importGroups += iType
			}
			prevGroup = iType
		}

		if !isValidImportGroups(importGroups) {
			invalidImports = append(invalidImports, path)
		}
		return nil
	})
	if err != nil {
		panic(err)
	}

	if len(invalidImports) == 0 {
		fmt.Println("good boy")
		return
	}

	fmt.Println("fix your imports, you son of a bitch")
	for _, i := range invalidImports {
		fmt.Println(i)
	}
}

func identifyImportType(project, imp string) string {
	imp = strings.TrimSpace(imp)
	aliasAndImport := strings.Split(imp, " ")
	imp = aliasAndImport[len(aliasAndImport)-1]
	switch {
	case imp == "":
		return " "
	case !strings.Contains(imp, "."):
		return "STD"
	case strings.HasPrefix(imp, "\""+project):
		return "LOC"
	default:
		return "EXT"
	}
}

func isValidImportGroups(importGroups string) bool {
	if strings.HasSuffix(importGroups, " ") || strings.HasSuffix(importGroups, " ") {
		return false
	}
	return strings.Contains("STD EXT LOC||STD LOC", importGroups)
}